Ay Mcdonald 4423-397 Pex-a Poly Insert Tee 1x1x3/4 in

Product Description

The AY MCDONALD 4423-397 is a PEX-A poly insert tee fitting used to split or branch a PEX-A water distribution line. It connects a 1-inch run to a 3/4-inch branch, making it a common transition fitting in residential and light commercial plumbing rough-ins. The poly insert design seats inside the PEX tubing and is secured with crimp or clamp rings, creating a watertight joint without soldering. Licensed plumbers and pipefitters install this fitting as part of PEX manifold systems, home-run layouts, and trunk-and-branch distribution configurations.

This fitting is suited for potable water supply systems, radiant heating distribution, and hydronic applications where PEX-A tubing is specified. The 1-inch by 1-inch by 3/4-inch sizing makes it appropriate for main-line branch-offs where a full-bore run must be maintained while reducing down to a 3/4-inch service leg. It is typically installed in wall cavities, crawl spaces, and mechanical rooms as part of a complete PEX piping system.

Key Features

• Poly insert tee construction compatible with PEX-A tubing
• 1-inch by 1-inch run with 3/4-inch branch outlet for common trunk-to-branch transitions
• Insert-style connection secured with crimp rings or clamp rings
• Suitable for potable water and hydronic heating applications
• Order increment of 1 for single-unit purchasing

Compatibility

Designed as an OEM-style replacement and standard fitting for PEX-A plumbing systems requiring a 1-inch by 1-inch by 3/4-inch tee configuration.

Installation Notes

Installation should be performed by a licensed plumber in accordance with local plumbing codes and the International Plumbing Code (IPC). Shut off the water supply and depressurize the line before cutting into any existing pipe. Use the appropriate PEX crimp or clamp tool rated for the tubing size to ensure a secure, leak-free connection. Inspect the insert seat and tube ends for burrs or debris before assembly.